JP2000055086A - Back torque limiter mechanism for clutch device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control clutch connecting force and a back torque set value with higher accuracy by energizing both clutch inners in a direction to be integrated and adjusting clearance between a subclutch inner and a pressure plate. SOLUTION: A subclutch inner 18 is energized to the side of a main clutch inner 17 located on a side opposite to a pressure plate 25 and clearance is provided between a right tip part of the subclutch inner 18 and an internal surface of the pressure plate 25. Therefore, a dimensional error of thickness of outer and inner friction plates 12, 13 or an integrated value of wear of the outer and inner friction plates 12, 13 does not affect clutch connecting force and back torque set value, and the friction plates 12, 13 always slide out by back torque at the set value. Because an adjusting bolt 34 adjusting clearance of a right tip part of an outer peripheral boss part 18b of the subclutch inner 18 and the pressure plate 25 is provided, the back torque set value can be set with accuracy by adjusting clearance, even when the dimensional error of the friction plates 12, 13 or wear amount is large.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch device for transmitting or interrupting rotation of a crankshaft to an input shaft of a transmission, in which excessive reverse torque is transmitted from a transmission side to a crankshaft side in a reverse direction. The present invention relates to a back torque limiter mechanism for avoiding the problem.

[0002]

2. Description of the Related Art As a back torque limiter mechanism in a conventional clutch device, for example, Japanese Patent Publication No. 61-96222
There is one shown in Japanese Patent Publication No. This is achieved by disposing an outer friction plate and an inner friction plate sequentially between a clutch outer connected to the crankshaft and a clutch hub (clutch inner) connected to the input shaft of the transmission, and The two friction plates are configured to be pressed against each other by a clutch spring by a pressure plate, the clutch hub is divided into two in the axial direction into a main hub and a sub hub, and the sub hub is connected to the main hub so as to be relatively movable in the axial direction. A cone spring is provided between the sub-hub and the main hub so as to bias the sub-hub so as to contact the pressure plate. A cam mechanism is provided between the sub-hub and the main hub to move the sub-hub toward the pressure plate when the back torque becomes excessive, thereby releasing the pressure contact force by the pressure plate.

[0003]

In the above-mentioned conventional clutch device, the set value of the spring force of the clutch spring and the cone spring determines the pressure contact force (clutch connection force) when the clutch is engaged and the back torque that causes slippage. The magnitude (back torque setting value) is managed, but the setting value of the spring force of the cone spring varies depending on the integrated value of the dimensional error of the thickness of all the friction plates.
Therefore, the conventional device has a problem that it is particularly difficult to manage the back torque set value. In particular, when each friction plate is worn by a long-term operation, the total wear amount of all the friction plates also affects the above-mentioned back torque set value.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is intended to provide a clutch device in which dimensional errors and wear of clutch plates (outer and inner friction plates) do not affect a set value of back torque. It is an object to provide a back torque limiter mechanism.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to an axial movement between a clutch outer connected to a crankshaft and a clutch inner connected to an input shaft of a transmission, together with the clutch outer. A possible outer friction plate and an inner friction plate that rotates together with the clutch inner and are movable in the axial direction are sequentially superimposed on each other, and the outer and inner friction plates are pressed against each other by a pressure plate or the pressing force is released. As a result, in the clutch device in which the rotation of the crankshaft is transmitted or interrupted to the transmission, the back torque transmitted in the opposite direction from the transmission is released, and excessive back torque is transmitted to the crankshaft. A back torque limiter mechanism that prevents the clutch inner from being engaged with the inner friction plate. The latch inner is divided into the main clutch inner axially sandwiching the outer and inner friction plates by the pressure plate connected to the input shaft, and the main and sub clutch inners are movably coupled in the axial direction. An urging means for urging the sub-clutch inner against the main clutch inner in the pressing direction, and moving the sub-clutch inner toward the pressure plate by the back torque to thereby move the pressure plate in the counter-pressing direction. It is characterized in that a back torque releasing means for moving and an adjusting means for adjusting a gap between the sub clutch inner and the pressure plate are provided.

[0006]

According to the back torque limiter mechanism of the clutch device according to the present invention, when a back torque of a predetermined value or more is input from the rear wheel to the input shaft of the transmission during deceleration, the back torque is released. By means, the sub-clutch inner moves to the pressure plate side and presses the pressure plate toward the counter pressure contact side (clutch disengagement side), whereby the pressure contact force is reduced and the outer and inner friction plates slide, causing excessive back torque. Is prevented from being transmitted to the engine side.

In the present invention, the sub-clutch inner is urged by the urging means toward the main clutch inner side, that is, in a direction in which the two clutch inners are integrated, and a gap between the sub-clutch inner and the pressure plate is provided. By adjusting the clearance to a predetermined value, the clutch connection force and the set value of the back torque are not affected by the dimensional error of the friction plate and the magnitude of the wear amount. The clutch engagement force and the back torque set value can be managed with higher accuracy.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 are views for explaining a back torque limiter mechanism of a multi-plate friction clutch device according to a first embodiment of the present invention. FIG. 1 is a sectional side view of the clutch device, and FIG. 3 is a front view of the inner portion of the main clutch as viewed from the outside of the vehicle, FIG.
FIG. 3 is a sectional view of a main part taken along line II-II of FIG. 2.

In FIG. 1, reference numeral 1 denotes a multi-plate type friction clutch device for a motorcycle which is configured to transmit or cut off rotation of a crankshaft to an input shaft 2 of a transmission, which is formed on a crankcase side. It is housed in the clutch housing 3 and is coaxially arranged at the outer end of the input shaft 2 on the transmission side.

The clutch device 1 includes a large reduction gear 5 meshed with a small reduction gear (not shown) formed on the crankshaft.
And a clutch inner 1 spline-coupled to an input shaft 2 of a transmission (not shown).
5, a large number of outer friction plates 12 and a large number of inner friction plates 13 are arranged alternately on top of each other.
Of the clutch inner 15 and the pressure plate 25 to press the outer and inner friction plates 12 and 13 against each other.
The pressure contact force is released by pressing and moving the 5 to the right in the figure.

The large reduction gear 5 comprises a gear main body 5a having meshing teeth on the outer periphery comprising a connecting pipe 9, a rivet 7, a spring damper 8 and the like, and a base plate via a damper mechanism for absorbing engine torque fluctuations. 5b. The base plate 5b has a cylindrical boss 5c.
Are rotatably mounted on the input shaft 2 with a collar 6b and a needle bearing 6a interposed therebetween.

The clutch outer 10 is made of aluminum die-cast and has a dish-shaped outer body 10 having an opening in the bottom wall.
a and a disc-shaped bottom plate 10b for closing the opening is formed as a whole with a rivet 10c to form a cup, and the boss portion 5c of the base plate 5b of the large reduction gear 5 is provided in the opening of the bottom plate 10. Is inserted, and the periphery of the boss 5c is joined to the opening edge of the bottom plate 10b by press-fitting the joining projection 5d. The inner peripheral surface of the bottom plate 10b is the input shaft 2
It is rotatably supported by a collar member 11a and a ball bearing 11b, which are spline-fitted to the shaft. As a result, the clutch outer 10 always rotates during engine rotation. Reference numeral 5e denotes an intermediate gear that is rotationally driven by the kick gear at the time of starting the kick, and rotates with the large reduction gear 5. 2b is a right main bearing of the input shaft 2.

The outer body 10 of the clutch outer 10
A plurality of split grooves 10d extending in the axial direction are formed at predetermined angular intervals on the inner peripheral surface of a, and are formed at predetermined angular intervals on the outer circumference of the outer friction plate 12 in the split grooves 10d. The projection 12a is engaged. Each outer friction plate 12
Are arranged at intervals in the axial direction and are movable in the axial direction. An inner friction plate 13 is disposed between each of the outer friction plates 12, and each of the inner friction plates 13 has a convex portion 13a formed at a predetermined angular interval on an inner peripheral surface thereof, as will be described later. The clutch inner 18 is engaged with a split groove 18c formed at a predetermined angular interval on the outer peripheral boss 18b of the clutch inner 18.

The clutch inner 15 is made of aluminum die-cast, and has an axially divided structure of a main clutch inner 17 and a sub clutch inner 18. The main clutch inner 17 is substantially disc-shaped, has a flange portion 17a on the outer peripheral portion with which the friction plate abuts, and an inner peripheral boss portion 17b is spline-fitted to the input shaft 2,
Further, it is fastened and fixed by a nut 19 so as not to move in the axial direction. As a result, the main clutch inner 17 always rotates integrally with the input shaft 2.

The above-mentioned sub-clutch inner 18 is
The outer peripheral edge of the outer peripheral boss 18b is formed integrally with the outer peripheral edge of the outer peripheral boss 18b, and the split grooves 18c are formed at predetermined angular intervals on the outer peripheral surface of the outer peripheral boss 18b. The inner peripheral surface of the portion 18a is the main clutch inner 1
7 is movably fitted in the inner peripheral boss portion 17b. The sub clutch inner 18 is urged by the urging means 23 toward the main clutch inner 17.

The urging means 23 implants six spring receiving pins 23a around the inner periphery of the outer boss portion 18b of the sub-clutch inner 18 at regular angular intervals, and implants the spring receiving pins 23a. The main clutch inner 17 is protruded to the rear side, and a biasing spring 23c is interposed between a spring seat 23b attached to the tip of the spring receiving pin 23a and the rear side of the main clutch inner 17. I have. As a result, the sub clutch inner 18 is urged toward the main clutch inner 17 by the spring force of the urging spring 23c, and the two clutch inners 17, 18 usually rotate integrally.

When a back torque of a predetermined value or more is input to the input shaft 2 between the main and sub clutch inners 17 and 18, the sub clutch inner 18 is moved rightward in the drawing. Six sets of cam mechanisms (pressing force releasing means) 22 are arranged at equal angular intervals. The cam mechanism 22 includes main and sub clutch inners 17 and 18.
Ball 20 between the cam surfaces 21a and 21b formed on the
When the main clutch inner 17 is relatively rotated in the direction of arrow A by the back torque, the sub clutch inner 18 is relatively moved in the direction of arrow B. Moving.

The pressure plate 25 is coaxial with the clutch inner 15, and is arranged so that its outer peripheral portion faces the flange portion 17 a of the main clutch inner 17. A guide cylinder 31 is fixed to the shaft core of the pressure plate 25 by an adjustment rod 32, and the guide cylinder 31 is slidably inserted into the guide hole 2 b of the input shaft 2. The adjustment rod 32 is connected to the guide cylinder 3
1, protrudes rightward from the pressure plate 25, and is fixed with a lock nut 33. A ball 29 is housed and arranged in the left end of the guide cylinder 31, and a pressing member 30a slidably inserted into the guide hole 2b of the input shaft 2 is in contact with the ball 29.
The release rod 30 connected to the pressing member 30a is coaxially arranged in the guide hole 2b of the input shaft 2. The left end of the release rod 30 is connected to a clutch lever mounted on a steering handle via an appropriate transmission mechanism,
By operating the clutch lever, the release rod 30 moves forward and backward.

The pressure plate 25 is urged toward the flange 17a side of the clutch inner 15 by six sets of urging mechanisms 26 arranged at equal angular intervals.
The biasing mechanism 26 inserts a clutch spring 28a into a spring receiving cap 28 mounted on the pressure plate 25, and connects the spring rod 27 to the main clutch inner 10b.
And a spring spring 27a is interposed between a spring seat 27a formed at the tip of the spring rod 27 and the spring receiving cap 28. Thus, the outer and inner friction plates 12 and 13 are always sandwiched between the flange portion 17a and the pressure plate 25 and are in pressure contact with each other.

The right end of the outer boss 18b of the sub-clutch inner 18 is opposed to the pressure plate 25 with a predetermined gap. The pressure plate 25 has an adjustment bolt 34 for adjusting this gap.
The adjusting bolt 34 is attached to the lock nut 3.
5 is fixed so as not to rotate.

Next, the operation and effect of the apparatus of this embodiment will be described. When normal running such as constant speed running or accelerated running is performed with the clutch connected, the outer and inner friction plates 12 and 13 are brought into contact with the pressure plate 25 and the main clutch inner 1 by the urging force of the clutch spring 28.
7 is pressed against the flange portion 17a. Accordingly, the rotation of the crankshaft is transmitted from the large reduction gear 5 to the clutch outer 1.
0, the outer, inner friction plates 12, 13 and the clutch inner 15 are transmitted to the input shaft 2 of the transmission, and transmitted to the rear wheels via the transmission.

When the clutch is disconnected, the relay rod 30 is moved in the direction of arrow F by operating the clutch lever.
As a result, the pressure plate 25 is moved to the clutch spring 28.
Is moved in the direction of arrow F against the spring force of the above, the pressure contact force between the pressure plate 25 and the flange portion 17a is released, the connection between the outer and inner friction plates 12, 13 is cut off, and the clutch is disconnected. Become.

During the normal running, a forward torque acts on the main clutch inner 17 from the sub-clutch inner 18 side. Therefore, in the cam mechanism 22, the rotational torque from the sub clutch inner 18 is transmitted to the main clutch inner 17 side via the cam ball 20 as it is, and the rotation is transmitted without any trouble.

On the other hand, during deceleration, a reverse torque (back torque) acts from the rear wheel side to the engine side. Therefore, in the cam mechanism 22, as shown in FIG. 3, the main clutch inner 17 fixed to the input shaft 2 rotates relative to the sub clutch inner 18 in the direction of arrow A, whereby the sub clutch inner 18 is pressed by the cam ball 20. And relatively moves in the direction of arrow B. When the amount of movement of the sub-clutch inner 18 exceeds the gap set by the adjusting bolt 34, the pressure plate 25 is pressed and moved toward the arrow F, and the pressure contact force of the outer and inner friction plates 12, 13 decreases. As a result, an appropriate slip between the two friction plates 12 and 13 occurs, preventing the engine from over-rotating and also preventing a situation where the engine brake is suddenly applied.

In this embodiment, the sub-clutch inner 18 is urged toward the main clutch inner 17 located on the side opposite to the pressure plate 25 so that the right end of the sub-clutch inner 18 and the inner surface of the pressure plate 25 are separated from each other. Since there is a gap between the outer and inner friction plates 12 and 13, the dimensional error of the thickness of the outer and inner friction plates 12 and 13 or the integrated value of the wear of the outer and inner friction plates 12 and 13 is determined by the set values of the clutch connection force and the back torque. Does not affect
Friction plates 12, 13 always with the back torque as set
Each other starts to slide.

In this embodiment, the adjusting bolt 34 for adjusting the gap between the right end of the outer boss 18b of the sub-clutch inner 18 and the pressure plate 25 is provided.
By adjusting the gap, the dimensional error of the friction plate,
Alternatively, even when the wear amount is large, the back torque set value can be set with high accuracy.

In this embodiment, the main and sub clutch inners 17, 18 and the friction plates are urged by the urging means 23 in the direction in which the friction plates are pressed against each other. Subassemblies 12 and 13 can be subassembled, and the assemblability is good.

FIGS. 4 and 5 show a second embodiment in which the urging mechanism 26 of the above embodiment is modified. The urging mechanism 26 ′ of the second embodiment has a structure in which the disc spring 38 is pressed against the pressure plate 25 by the spring rod 27.

Here, the disc spring 38 has a spring force of FIG.
As shown in the deflection amount characteristic, the clutch spring 28a composed of the coil spring in the embodiment of FIG. 1 increases the spring force in proportion to the deflection amount (see the characteristic curve a), whereas in the region where the deflection amount is small, The spring force does not increase so much, and shows a characteristic in which the spring force suddenly increases as the amount of deflection increases (see a characteristic curve b).

In the second embodiment, since the disc spring 38 having the above-described spring force-deflection amount characteristic b is employed, the cam ball 20 and the cam surfaces 21a, 2a in the cam mechanism 22 are used.
The durability can be improved by reducing the wear amount of 1b. That is,
In FIG. 3, when the main clutch inner 17 relatively rotates in the direction of arrow A due to the back torque, the sub clutch inner 18 relatively moves in the direction of arrow. At this time, the cam ball 20 relatively rolls on the cam surfaces 21a and 21b, and the amount of this rolling decreases as the inclination angle of the cam surface increases.

In the second embodiment, since the disc spring 38 has a characteristic that the spring force is small in the initial stage of the input of the back torque, the inclination of the cam surfaces 21a and 21b can be steeper than in the first embodiment. Therefore, the relative rolling amount is reduced, and as a result, the wear amount is reduced and the durability can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional side view of a multi-plate friction clutch device according to a first embodiment of the present invention.

FIG. 2 is a front view of an inner portion of a main clutch of the clutch device as viewed from the outside in the axial direction.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a sectional side view of a multi-plate friction clutch device according to a second embodiment of the present invention.

FIG. 5 is a view showing a spring force-deflection amount characteristic of a clutch spring.

[Explanation of symbols]

 Reference Signs List 1 multi-plate friction clutch device 2 input shaft 10 clutch outer 12 outer friction plate 13 inner friction plate 15 clutch inner 17 main clutch inner 17a flange portion 18 sub-clutch inner 22 cam mechanism (back torque releasing means) 23b biasing spring (biasing spring) Means) 25 Pressure plate 34 Adjusting bolt (Adjusting means)

Claims (1)

[Claims] An outer friction plate, which rotates together with the clutch outer and is movable in the axial direction, between the clutch outer connected to a crankshaft side and a clutch inner connected to an input shaft side of a transmission, and the clutch. The inner friction plate, which rotates together with the inner member and is movable in the axial direction, is sequentially superposed and arranged, and the outer and inner friction plates are pressed against each other by a pressure plate or the pressure contact force is released to shift the rotation of the crankshaft. In a clutch device that transmits or disconnects to the device side, a back torque transmitted in the opposite direction from the transmission side is released to prevent excessive back torque from being transmitted to the crankshaft side. A back torque limiter mechanism, wherein the clutch inner is connected to a sub-clutch inner with which the inner friction plate is engaged. The outer plate and the inner clutch plate are divided into a main clutch inner for axially sandwiching the outer and inner friction plates with the pressure plate, and the main and sub clutch inners are connected so as to be relatively movable in the axial direction. Urging means for urging the inner against the main clutch inner in the direction in which the outer and inner friction plates are pressed, and moving the sub-clutch inner toward the pressure plate by the back torque to thereby counter-press the pressure plate. A back torque limiter mechanism for a clutch device, comprising: a back torque release unit for moving the clutch in the direction; and an adjusting unit for adjusting a gap between the sub clutch inner and the pressure plate.